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    SubjectRe: [PATCH v3] x86: clear incorrectly forced X86_FEATURE_LAHF_LM flag
    On Tue, Aug 11, 2009 at 04:37:56PM +0200, Mikael Pettersson wrote:
    > Since the BIOS apparently wrote some MSR to get LAHF_LM incorrectly
    > reported by CPUID, would it be possible to also correct that MSR so
    > that applications that execute CPUID get the correct feature flags?

    That's a good catch, actually. We have to turn off that bit in the cpuid
    leaf too if the CPU doesn't support the instructions so that cpuid info
    is consistent. LAHF/SAHF support in 64bit mode has to be cpuid-checked
    prior to using them so that info has to be correct.

    @Kevin: willing to try a patch or two?


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